Yes they would, people already use alternative coins. And if they have a use, people would use new ones. Like the gold in World of Warcraft, I bet it could be considered an online currency, because I bet there are people trading REAL world stuff (I know they at least trade money for gold).
If someone invented a game that used their new currency, then bam, the currency is at least as valuable as their game. Then make a forum, and make people pay coins as membership fees, bam, two real world applications for your coin. Then start selling candy bars for coins, bam, now people are wondering where to get coins so they can get a candy bar.
I am not talking about making it from thin air, is your point that you do not think I have the ability to build capitol? Because I do, I am not "proposing" plans, I am presenting them.
No I have not seen zeitgeist, but everyone tries to make me watch that video and they think it's awesome. I have seen the first 20 minutes though and I learned all that stuff when I was like 13.
What you're describing is similar to the Venus Project showcased in Zeitgeist (robosocialism); it would be in your best interest to watch all 3 movies, so you have a better idea of what an RBE would work like.
You're missing the point tho; lets say we had A-Coin. And B-Coin. And C-Coin. And D-Coin. So now you have 4 different wallets for 4 different coins.
Multiply that by a million and we have a problem. Not only is it hard to keep track of, but each individual coin would be nearly worthless. It's like government printing out more money. Bitcoin is scarce because it has a limit; however, 1 million incarnations of Bitcoin, and counting, are not scarce. Because of this, people will stick to a very small number of coins, and will likely mine those coins, except they can't, because everyone is, so we're back at the problem described earlier. I've got a million Mikecoins and I'd be lucky to get my mum to take them to buy a sandwich off her. Now she's got a million Mikecoins that nobody wants; imagine this, except with all the people in the world, and we're having a problem keeping everyone on the same page. People will naturally flock to the same few coins, and if not for better coins, coins that have been around longer, and are more widely adopted, just because they can use them for stuff.
I can't buy a thing with my PPcoins btw. I got quite a few of them. I can, however, trade them for one or two bitcoins. That's PPCoin, and it's been around for a couple years. Imagine creating a new one every other week. They'd never take off. We simply have no need for that many altcoins. Altcoins are great, but a million of them is just way too much. You won't find anyone to take fj8e92qjr839qCoin, the 432,398th coin to be created. As I said, again, it's an attempt to create wealth out of nothing.
Also, WoW gold is worth next to nothing. It has value because it's a pain in the ass to collect and people are lazy (they're also suckers, but, that's nothing new.) It is, however, unlimited in supply, so it's a lot like fiat, except much worse. Nobody is buying candy bars with WoW gold because of this, nor are they paying their subscriptions with WoW gold because the devs are smarter than to accept their own virtual currency that's unlimited in supply. Finally, because WoW gold is earned in-game, it's nearly impossible to get enough people using it, and it's insecure, for your account can be stolen, shut-down, and any mod can create themselves WoW gold on the spot. Try paying for your grocery bill with it; never happen. That's essentially what will happen with enough offshoots of Bitcoin; the altcoins become worthless.
But as I said before, when there's no work, there's no economy. So the point is moot.